Epoxidation of cyclopentene by a low cost and environmentally friendly bicarbonate/peroxide/manganese system

Abstract

The system hydrogen peroxide/sodium bicarbonate/manganese sulfate was used for the first time to epoxidize cyclopentene. Effects of parameters such as type and amount of solvent, ratio of hydrogen peroxide and manganese sulfate to cyclopentene, presence of additives, and reaction time and temperature on the selectivity to cyclopentene oxide were evaluated. Gas chromatography was used to quantify residual cyclopentene and produced cyclopentene oxide using the internal standard method. Type and amount of solvent, addition method, and temperature were important factors to increase the selectivity to cyclopentene oxide. Unlike previous reports on epoxidation of different substrates, additives like sodium acetate and salicylic acid did not improve the selectivity to cyclopentene oxide. One time, single-step addition of hydrogen peroxide/sodium bicarbonate to the solution of cyclopentene/solvent/manganese

Oxidation of Cyclopentene with Manganese Oxides Octahedral Molecular Sieves with Layer and Tunnel Structures

“…Higher temperature and molar ratio H 2 O 2 /CPE under heterogenous conditions were not tested since under homogeneous conditions for the epoxidation of CPE in the system Mn(II)/ DMF/NaHCO 3 /H 2 O 2 increasing temperature and molar ratio H 2 O 2 /CPE decreased the selectivity of the epoxidation. [24] The presence of a dark precipitate after 30 min of reaction, was reported in the homogenous epoxidation of CPE. [24] This dark precipitate could be related either to the precursors or to birnessite (OL-1) since manganese sulfate in basic media and under oxidant conditions has been used to synthesize OMS-2, the transformation reported was from Mn 2 + to Mn 3 + rich feitknechtite to birnessite (OL-1) and after calcination to OMS-2.…”

“…[24] The presence of a dark precipitate after 30 min of reaction, was reported in the homogenous epoxidation of CPE. [24] This dark precipitate could be related either to the precursors or to birnessite (OL-1) since manganese sulfate in basic media and under oxidant conditions has been used to synthesize OMS-2, the transformation reported was from Mn 2 + to Mn 3 + rich feitknechtite to birnessite (OL-1) and after calcination to OMS-2. [25,45,46] The active sites required for the epoxidation of CPE are formed in situ during the homogenous process and could be Scheme 1.…”

“…The epoxidation of CPE in a homogeneous system using the sodium bicarbonate/hydrogen peroxide system (BAP) has been reported previously with a 72 % conversion of CPE and a 56 % selectivity to CPO. [24] Heterogeneous catalysis is more advantageous than homogeneous catalysis. Herein, we report the use of OL-1, OMS-2 and OMS-1 as synthesized, and impregnated with sodium tungstate as heterogeneous catalysts in the epoxidation of CPE using the sodium bicarbonate/ hydrogen peroxide system (BAP).…”

Electrochemical Epoxidation Catalyzed by Manganese Salen Complex and Carbonate with Boron-Doped Diamond Electrode

“…Carbonates have often been used as activators for oxidation reactions with hydrogen peroxide, including epoxidation reactions [ 20 , 21 , 22 , 23 , 24 ]. It has been reported that percarbonate is involved in manganese-catalyzed alkene epoxidation reactions using hydrogen peroxide in carbonate or bicarbonate aqueous solutions [ 20 , 21 , 24 , 25 , 26 ]. Burgess and co-workers proposed the involvement of manganese η 2 -peroxycarbonate complexes to facilitate the cleavage of the O–O bonds of percarbonate ions.…”